The conventional design of radiator cores has remained virtually unchanged for decades. Specially shaped generally oval tubes are provided, to which are attached a plurality of fins at spaced intervals. At each end of each tube, each tube is received in a header plate which is, in turn, enclosed to form a header tank.
Standard radiator design requires that the ends of the tubes be soldered into the header plate, and that the fins be soldered to the tubes. This requirement for soldering has meant that, for very many years such radiator cores were made of copper. This is relatively expensive and, in addition, is liable to corrosion caused by salt and other harmful chemicals, thrown up from the road.
Other disadvantages of standard radiator design in the past have been, the restrictions on the volumetric flow of coolant through the radiator, and also the method by which the radiator was mounted in the automobile. Generally speaking, standard automobile radiator design in the past involved the use of tubes which were of a flattened oval in shape, with the fins being in the form of concertina folded strips of copper, soldered between two adjacent tubes. The oval shaping of the tubes caused restrictions on the volumetric flow of coolant through the tubes, which reduced the heat exchange efficiency of the radiator.
In addition, copper is relatively heavy, and vehicle design increasingly requires the use of lightweight materials. Techniques for soldering lightweight material such as aluminum have been developed, so that it is now possible to manufacture radiator cores from aluminum. However, these techniques involve a very substantial investment in equipment so that there are in fact very few such installations, and almost all of them manufacture radiators for the OEM market. The servicing of defective copper radiators, in the past, using conventional soldering techniques has been carried on by automobile repair shops, which are readily available, and which are highly competitive. Consequently in the event of a copper radiator failing, it was a relatively simple and reasonably inexpensive matter to have it serviced. However, these automobile repair shops are generally speaking unable to make the necessary investment in capital equipment to service soldered aluminum radiators. Consequently a vehicle owner with a defective soldered aluminum radiator must, generally speaking, go back to the automobile dealer who will, in turn, be forced to install a completely new OEM or equivalent radiator, at a very considerable cost, and some possible delay.
One of the problems that arises particularly in automobile radiators, is the need for some form of attachment bracket whereby the core can be secured to the automobile typically at the forward end of the engine compartment. Another problem arises from the need to maximize the efficiency of the heat transfer capabilities of such a radiator core, for a given size and weight of core.
In the design of automobiles, cost, frontal area, and weight, are highly significant factors and it is, therefore, desirable to maximize the efficiency of such a radiator core, for a given size of core.
A further factor in the design of such a radiator core, which affects both its weight and its efficiency, is the design and shaping of the cooling fins, and also the spacing between the cooling fins, and also the volumetric coolant flow.